308 replies to this topic

[McMini 22]

I would be worried that if I made one it would be heavier than a standard frame. The tendency would be to over engineer it.

[McMini 22]

I got the subframe out last night and it's not good news -

 

 

 

This is further gone than I was hoping.  I could repair it but it's the rust in all of the bits I can't see that's putting me off.  So it's time for a new one and a £200 bill that I was not budgeting for!  I take it after-market ones are OK?  I'm not shelling out £450 for a genuine one as for that amount I would rather make a tubular one.

 

 

On the plus side the floor is in remarkable condition and is all original.  Heelboard looks in good shape.

 

 

Only a couple of spots of surface rust on the boot floor where the exhaust has degraded the rust protection.  Check out how rust free that back panel is! 

 

 

[lawrence]

Could be worth you taking one side of the rusted bit off then you can inspect the webbing on the inside also?
That's what I did for mine before confirming it was dead. It's worth a look either way :)

[fuzzy-hair-man]

What about a rear beam subframe and trailing arms with coil overs? If it's the back section that's corroded then may be able to use the front where it bolts to the heal board.

[McMini 22]

Could be worth you taking one side of the rusted bit off then you can inspect the webbing on the inside also?
That's what I did for mine before confirming it was dead. It's worth a look either way :)

The web is definitely rusted and has holes in it.  I could cut out all the rust and replace with sound metal and I'm confident it would be strong and I'd make a good job.  The problem is the rust that you can't see.  In the seams and triple sections.  Even sandblasting won't get that out.  A new one has been ordered with fitting kit and also new radius arm pins and bearings.

 

 

What about a rear beam subframe and trailing arms with coil overs? If it's the back section that's corroded then may be able to use the front where it bolts to the heal board.

 

I did think about making a beam.  However, I want to keep the suspension standard (well rubber donuts and hilos).  I also want a tow bar on it so the only option for fabricating something would be a full tubular subframe.  I would use square bar if I was making something up.  Maybe a project for the future (maybe even a sideline business!) but time is marching on and this build is not going as fast as I would like.

 

My new subframe will be stripped of the paint it is supplied in and painted with Epoxy Primer and then a coat of 2K black.  After that it's waxoyl or dynotrol all over and in the box sections.  As this car will be more or less a daily driver I am doing my best to slow down the return of the inevitable rust that seams to love attacking our wee Minis!

[paulrockliffe]

I have a tow bar that I've just found tucked under my rear subframe and removed. Message me if you'd like to see some pictures?

[charlieb150]

Just seen this looks very good like the look of the subframe 👍

[McMini 22]

Just seen this looks very good like the look of the subframe 👍

Cheers. If only everyone appreciated my engineering abilities! Long story.

[lawrence]

I understand with regards to the rear frame, sometimes for safety's sake it's not worth it, plus all the faff with alignment etc.

[McMini 22]

I got the subframe stripped last night but had one big problem. Most of the bolts on the radius arm end plates sheared off, which was good. However, one of them decided it would be more fun for me if the captive nut on the inside shears off allowing tho bolt to spin.



I cut the subframe to get access but it is impossible to get a socket on the nut as there is another captive nut in the way. I managed to wedge a 13mm crow foot spanner in there and luckily the bolt sheared.

[benm]

Chisel off and weld a new one on! ive converted my rear subframe to all metric fittings

[micraminiman]

Chisel off and weld a new one on! ive converted my rear subframe to all metric fittings

 

Definately a good idea Ben. Im slowly turning everything I can into metric on the beastie.

[McMini 22]

Chisel off and weld a new one on! ive converted my rear subframe to all metric fittings

 
Definately a good idea Ben. Im slowly turning everything I can into metric on the beastie.

Yes but not a good idea if I'm fitting a new subframe!

Radius arms are in work with me today as I need the oxygen acetylene on the brake adjusters.

[McMini 22]

This week I have been working on the new rear subframe. I am stripping all the paint off and modifying the rear cross bar by boxing it in. I'm also adding a few more welds and generally making it a bit tidier. Photos later.

I started scraping the rustproofing off the underside. It's taking ages. Found some holes that need a bit of welding. It's that bit where all the muck sits on top of the subframe.



This is it from the inside. The inner sill looks mint except for this one wee bit.

[McMini 22]

Been busy getting the back end welded up and sorted. I was in the garage til 1am getting the epoxy primer on. I'm hoping to get some colour and lacquer on tomorrow night.